Field of the Invention
The present invention relates to an image forming apparatus capable of shifting to a high-speed activatable state when the OFF operation of a power switch is performed, a control method for the image forming apparatus, and a storage medium.
Description of the Related Art
Image forming apparatuses and information processing apparatuses of recent years have had multiple functions and, therefore, have a problem in taking longer time from the operation of a power switch by a user to an operable state in which the user can actually operate the apparatus.
Some apparatuses have a function called “suspend” (suspend mode) to deal with such a problem. When a user performs the OFF operation on a power switch, the operation of a program in execution is suspended by the suspend function such that the program can return to an operation state which is substantially the same as the current operation state.
Moreover, some apparatuses have a function called “resume”. This resume function activates the apparatus in an operation state which is substantially the same as the state at the time of termination of a preceding operation when a user performs the ON operation on a power switch. That is, the operation state returns to a preceding state when the user turns on the power switch.
According to the suspend function, the image forming apparatus in a normal operation mode can shift to the suspend mode, which causes an operation of each unit to be suspended, while the apparatus remains in a state immediately before suspension of the operation.
According to the resume function, moreover, the image forming apparatus in the suspend mode can return to the normal operation mode in a state immediately before shifting to the suspend mode.
Thus, these functions enable the image forming apparatus, such as a digital multifunction peripheral, to be activated at high speed, thereby promptly returning the image forming apparatus to a preceding operation state.
Moreover, the high-speed activation technique for retaining these memory values has a problem in which when the apparatus is shifted to the suspend mode during execution of processing, time elapses while processing is being interrupted.
Japanese Patent Application Laid-Open No. 11-3006 discusses an image forming apparatus which remains in a power-saving shift reserved state until a predetermined time elapses even when a power-saving shift key is operated.
If the high-speed activation technique retaining a memory value, for example, a suspend mode, is used for a power switch of the apparatus, a shift of the apparatus to the suspend mode during execution of processing such as a job causes the following phenomena.    1) immediately after the power supply is turned on, a job interrupted by power off is executed.    2) immediately after the power supply is turned on, a job interrupted by power off is displayed as an error.
Since the power switch is primarily used as a function of turning off the apparatus, the job interrupted by the switch-off should not be executed.
Moreover, even when the apparatus remains in the power-saving shift reserved state until a predetermined time elapses in spite of operation of the power-saving shift key as discussed in Japanese Patent Application Laid-Open No. 11-3006, similar problems may occur in a case where a job in execution or a job on standby is not completed within a predetermined time period.